This invention relates to a system for purifying a liquid (water) utilizing low grade heat, heat at or near the temperature range in which man and other life forms live.
The Department of Energy in the United States and similar governmental departments in other nations throughout the world have since their creation dedicated their scientific genius to finding new ways to provide energy from new energy sources not commonly used for the past ten to fifteen decades. The recent world-wide oil crisis brought into focus the increasing demand for energy in this country and elsewhere. In considering the demand for increased quantities of water for our cities and agriculture needs, it occurred to me that better lower level energy means might be employed to convert normally unusable salty or brackish water to pure water for use in areas of the world that presently have copious amounts of unusable water, examples of lands that have in or adjacent to them large quantities of brackish water include: Saudi Arabia, southern and western parts of Iran, North Africa, Southwest Africa, West and Southwest Australia, west side of Mexico (such as the Peninsula of Mexico, Baja), the Sonora Gran Desert and many hundreds of the Pacific and Atlantic Ocean Islands and the southwest and western states of the United States. A new type of water purification apparatus can overcome these deficiencies and provide ample amounts of fresh water. The water purification apparatus of this invention is best suited for dry, warm to hot arid areas where little or no fresh water is available, yet there are large amounts of brackish or contaminated water nearby.
An object of the present invention is to provide a novel means for purifying large quantities of brackish or contaminated water into fresh (pure) water at very low external energy input of the conventional type by using the warm to hot (65.degree. F. to 150.degree. F.) arid conditions available to power the water purification apparatus. The water quality is potable and should at least equal the best of water systems now used in the United States of America.
Another object of the present invention is to provide an improved system for producing single or multistage distilled liquid by using the weight of the liquid in a gravitational field to perform distillation by forming a vacuum of such an extent that, at a reduced pressure, the vapor pressure of the liquid, in one application, water, will boil at a substantially lower temperature. Liquid (water) is pumped to a height exceeding its ability to maintain liquid form when in the earth's gravitational field when the column or columns are closed at the top and all noncondensables are vented at the top of the column or columns and then the liquid is allowed to drop in the column or columns due to the gravitational forces exerted on the water (liquid) molecules. According to the laws of nature as defined by the laws of thermodynamics one can now design a water purification plant for vaporizing a liquid using the heat from the ambient air, solar radiation, low temperature geothermal heat or any other low grade heat (low temperature heat) and using blackbody radiation or using the wet bulb temperature or both blackbody and wet bulb temperature in these dry arid areas of the world to provide a predetermined .DELTA.T to perform distillation.
The distillation system of the present invention requires a minimum of two substantially vertical columns (vessels) which exceed the height which a liquid (water) can maintain itself as a liquid at a given pressure and temperature. A second vertical column (vessel) will be used to condense the vapor being formed from the first vertical vessel or vertical column.
The second embodiment of the invention is for a minimum of two vertical columns of water, one brackish and the other single stage distilled liquid, to cycle from their lower reservoirs (forming liquid seals) to the top of their respective columns at a predetermined rate in one configuration. Liquid (distilled water) is pumped from a lower level to the top of a second column where all noncondensables are vented to the atmosphere, then pump means for the brackish water is activated and the brackish water is pumped from a lower level to the top of the first column where all remaining noncondensables from the first column, as well as the vapor crossover means are vented to the atmosphere. Vapor crossover means has a selectively isolation means between the first vertical elongated column and the second vertical elongated column. Said vapor-liquid isolation means prevents cross contamination between the second vertical column of distilled water and first vertical elongated column of brackish water when cycling and recharging the distillation plant. The first and second vertical elongated columns have liquid seal means at the base of each column which also act as liquid reservoirs.
A third embodiment of the invention, the distillation plant has a self cleaning internal device to maintain good heat transfer and kept relatively free of deposits in the first column which performs the conversion of liquid to vapor of the media (water) for distillation.
A fourth embodiment of the invention, is back flushing of the feedstock in the first vertical column which is now essentially free of most water born living organisms due to the rapid change from a higher absolute pressure to a lower absolute pressure caused during back flushing of first vertical column, charging of first vertical column and rapidly going to subbaric pressure developed during evaporation which substantially explodes or ruptures the living organism's cellular structures, thus killing them without the aid of materials normally called insecticides or poisons. It should be noted that this process does not contaminate the environment.
A fifth embodiment of the invention, is radiating the vapor crossover means or radiating the top portion of the first vertical elongated column or radiating combination the first vertical column and the vapor crossover means by mercury vapour lamps, xenon lamps, hydrogen arc lamps, microwave bombardment, X-ray, Beta rays, Gamma rays, Alpha rays or any combination radiation of sufficient density and exposure time to be totally lethal for complete destruction of any microorganisms passing through this chamber or chambers when such chamber or chambers are in direct communication to the distilled water. It should also be noted that treatment of highly dangerous bacteria contaminated waste water may require radiation of the type described.
A sixth embodiment of this invention encompasses control means of said first vertical elongated column or columns and second vertical elongated column or columns for operatively sequentially controlling said pump means and temperature of said vertical elongated columns.
Other objects and advantages of the present invention will be made more apparent hereinafter.